From bd4a40b57b13907b4fe01b6c605be56d8f3733fe Mon Sep 17 00:00:00 2001 From: Karl Komierowski Date: Wed, 10 Aug 2011 15:09:43 +0200 Subject: mfd: Refactor ab8500 GPADC API, add raw access Refactor the GPADC interface to avoid bugs in calling code: - ab8500_gpadc_[convert|read_raw|ad_to_voltage] clarifies each functions use case, *convert wraps *read_raw, and we can access raw ADC values properly. - Renamed gpadc function arguments from "input" to "channel" to clarify use, so we don't get confused again. Signed-off-by: Kalle Komierowski Reviewed-by: Mattias Wallin Reviewed-by: John Beckett Signed-off-by: Linus Walleij Signed-off-by: Samuel Ortiz --- drivers/mfd/ab8500-gpadc.c | 56 +++++++++++++++++++++++++++++++++++----------- 1 file changed, 43 insertions(+), 13 deletions(-) (limited to 'drivers') diff --git a/drivers/mfd/ab8500-gpadc.c b/drivers/mfd/ab8500-gpadc.c index f16afb234ff9..e985d1701a83 100644 --- a/drivers/mfd/ab8500-gpadc.c +++ b/drivers/mfd/ab8500-gpadc.c @@ -143,12 +143,15 @@ struct ab8500_gpadc *ab8500_gpadc_get(char *name) } EXPORT_SYMBOL(ab8500_gpadc_get); -static int ab8500_gpadc_ad_to_voltage(struct ab8500_gpadc *gpadc, u8 input, +/** + * ab8500_gpadc_ad_to_voltage() - Convert a raw ADC value to a voltage + */ +int ab8500_gpadc_ad_to_voltage(struct ab8500_gpadc *gpadc, u8 channel, int ad_value) { int res; - switch (input) { + switch (channel) { case MAIN_CHARGER_V: /* For some reason we don't have calibrated data */ if (!gpadc->cal_data[ADC_INPUT_VMAIN].gain) { @@ -232,18 +235,46 @@ static int ab8500_gpadc_ad_to_voltage(struct ab8500_gpadc *gpadc, u8 input, } return res; } +EXPORT_SYMBOL(ab8500_gpadc_ad_to_voltage); /** * ab8500_gpadc_convert() - gpadc conversion - * @input: analog input to be converted to digital data + * @channel: analog channel to be converted to digital data * * This function converts the selected analog i/p to digital * data. */ -int ab8500_gpadc_convert(struct ab8500_gpadc *gpadc, u8 input) +int ab8500_gpadc_convert(struct ab8500_gpadc *gpadc, u8 channel) +{ + int ad_value; + int voltage; + + ad_value = ab8500_gpadc_read_raw(gpadc, channel); + if (ad_value < 0) { + dev_err(gpadc->dev, "GPADC raw value failed ch: %d\n", channel); + return ad_value; + } + + voltage = ab8500_gpadc_ad_to_voltage(gpadc, channel, ad_value); + + if (voltage < 0) + dev_err(gpadc->dev, "GPADC to voltage conversion failed ch:" + " %d AD: 0x%x\n", channel, ad_value); + + return voltage; +} +EXPORT_SYMBOL(ab8500_gpadc_convert); + +/** + * ab8500_gpadc_read_raw() - gpadc read + * @channel: analog channel to be read + * + * This function obtains the raw ADC value, this then needs + * to be converted by calling ab8500_gpadc_ad_to_voltage() + */ +int ab8500_gpadc_read_raw(struct ab8500_gpadc *gpadc, u8 channel) { int ret; - u16 data = 0; int looplimit = 0; u8 val, low_data, high_data; @@ -278,9 +309,9 @@ int ab8500_gpadc_convert(struct ab8500_gpadc *gpadc, u8 input) goto out; } - /* Select the input source and set average samples to 16 */ + /* Select the channel source and set average samples to 16 */ ret = abx500_set_register_interruptible(gpadc->dev, AB8500_GPADC, - AB8500_GPADC_CTRL2_REG, (input | SW_AVG_16)); + AB8500_GPADC_CTRL2_REG, (channel | SW_AVG_16)); if (ret < 0) { dev_err(gpadc->dev, "gpadc_conversion: set avg samples failed\n"); @@ -292,7 +323,7 @@ int ab8500_gpadc_convert(struct ab8500_gpadc *gpadc, u8 input) * charging current sense if it needed, ABB 3.0 needs some special * treatment too. */ - switch (input) { + switch (channel) { case MAIN_CHARGER_C: case USB_CHARGER_C: ret = abx500_mask_and_set_register_interruptible(gpadc->dev, @@ -359,7 +390,6 @@ int ab8500_gpadc_convert(struct ab8500_gpadc *gpadc, u8 input) goto out; } - data = (high_data << 8) | low_data; /* Disable GPADC */ ret = abx500_set_register_interruptible(gpadc->dev, AB8500_GPADC, AB8500_GPADC_CTRL1_REG, DIS_GPADC); @@ -370,8 +400,8 @@ int ab8500_gpadc_convert(struct ab8500_gpadc *gpadc, u8 input) /* Disable VTVout LDO this is required for GPADC */ regulator_disable(gpadc->regu); mutex_unlock(&gpadc->ab8500_gpadc_lock); - ret = ab8500_gpadc_ad_to_voltage(gpadc, input, data); - return ret; + + return (high_data << 8) | low_data; out: /* @@ -385,10 +415,10 @@ out: regulator_disable(gpadc->regu); mutex_unlock(&gpadc->ab8500_gpadc_lock); dev_err(gpadc->dev, - "gpadc_conversion: Failed to AD convert channel %d\n", input); + "gpadc_conversion: Failed to AD convert channel %d\n", channel); return ret; } -EXPORT_SYMBOL(ab8500_gpadc_convert); +EXPORT_SYMBOL(ab8500_gpadc_read_raw); /** * ab8500_bm_gpswadcconvend_handler() - isr for s/w gpadc conversion completion -- cgit v1.2.3